this is a good move and–as the article notes–was suggested by a sortition-based climate commission France did a few years back. they suggested a higher limit of 4 hours, but 2.5 is still pretty good:

France’s Citizens’ Convention on Climate, which was created by President Emmanuel Macron in 2019 and included 150 members of the public, had proposed scrapping plane journeys where train journeys of under four hours existed.